Technical Field
The present invention relates to a backpack working machine, and for example, relates to a backpack air-blow working machine for performing a variety of operations by driving a blower with an engine to blow air while being carried on the operator's back.
Background Art
Conventionally, hand-guided air-blow working machines (for example, Patent Document 1) and backpack air-blow working machines (for example, Patent Document 2) are known as air-blow working machines for performing an operation of gathering fallen leaves, rubbishes, and the like by driving a blower with a drive source, such as an engine, to blow air.
Among the aforementioned air-blow working machines, the hand-guided air-blow working machine has a configuration in which a drive source for driving a blower for blowing air, a fuel tank that stores a fuel to be supplied to the drive source, and the like are integrally attached to the blower. Thus, the operator is able to perform the aforementioned operation while carrying the air-blow working machine by gripping a handle portion that is provided above the blower, for example.
Meanwhile, the backpack air-blow working machine typically has a configuration in which, as disclosed in Patent Document 2, a blower is mounted on a backpack frame with a vibration isolation device, such as a spring suspension, interposed therebetween, and a drive source for driving the blower is attached to the blower, and further, a fuel tank that stores a fuel to be supplied to the drive source is attached to the backpack frame. Thus, the operator is able to perform the aforementioned operation while carrying the air-blow working machine on his/her back with shoulder straps and the like that are provided on the backpack frame. As described above, in the conventional backpack air-blow working machine, the comfort of the operator who uses the air-blow working machine is improved and a load imposed on the vibration isolation device is reduced by mounting the drive source (i.e., engine) and the blower, which can be sources of vibration, on the backpack frame with the vibration isolation device interposed therebetween, while attaching the fuel tank, which is not a source of vibration, directly to the backpack frame, thereby reducing the weight of the constituent portion that is connected to the vibration isolation device attached to the backpack frame.
However, when the drive source is mounted on the backpack frame with the vibration isolation device interposed therebetween while the fuel tank is directly attached to the backpack frame, there is a problem in that the relative positions of the drive source and the fuel tank may change due to vibration and the like of the drive source when the drive source is in use (in particular, when the drive source starts to be used), for example, and thus, a load may be imposed on a fuel pipe for supplying a fuel from the fuel tank to the drive source.
To address such a problem, Patent Document 3 discloses a backpack air-blow working machine with a configuration in which a blower is mounted on a backpack frame with a vibration isolation device made of rubber interposed therebetween, and a drive source and a fuel tank are integrally attached to the rear surface of a fan casing of the blower.